Stephen HawkingCambridge University physicist and author of popular science books. Hawking is severely disabled from motor neuron disease.

Jack KempRepublican politician and retired professional football player who passed away in May. A longtime member of the House of Representatives, Kemp was the party's 1996 vice-presidential candidate.

Senator Edward KennedyYounger brother of President John F Kennedy and Senator Robert Kennedy, Kennedy is known as a "liberal lion" in the US Senate for his championing of healthcare reform and civil rights.

Billie Jean KingRetired professional tennis player and one of the first openly lesbian sports figures. King defeated former number one player Bobby Riggs in the celebrated 1973 "battle of the sexes" match.

Reverend Joseph LoweryCivil rights leader and co-founder with Martin Luther King Jr of the Southern Christian Leadership Conference. Lowery gave the benediction at Barack Obama's inauguration.

Joe Medicine CrowThe last living war chief of the American Indians of the US Great Plains, according to the White House, and the author of seminal works of American Indian culture and history. While a soldier in the second world war, Medicine Crow stole 50 Nazi SS horses from a German camp.

Harvey MilkThe first openly gay elected official of a major city, Milk, a San Francisco supervisor, was assassinated in 1978. He is revered as a founder of the gay rights movement.

Sandra Day O'ConnorThe first woman on the US supreme court, appointed by President Ronald Reagan.

Sidney PoitierThe first African-American to win an Oscar for best actor, Poitier starred in the first mainstream movies to portray romantic interracial relationships.

Chita RiveraA prominent Hispanic singer and actress, Rivera played Anita in the film of West Side Story. She has won two Tony awards and been nominated seven more times.

Mary RobinsonFirst female president of Ireland, and a former UN high commissioner for human rights.

Desmond TutuA South African anti-apartheid leader and Anglican archbishop emeritus. Won the Nobel peace prize in 1984 for his efforts at racial reconciliation.

Muhammad YunusPioneer of microloans – small, low-interest loans to the poor extended without collateral. Yunus won the Nobel peace prize for his Grameen Bank's efforts in his native Bangladesh and elsewhere.